Curt T-Connector Vehicle Wiring Harness with 4-Way Flat Trailer Connector
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2010 Mini Cooper
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2010 Mini Cooper
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Wiring up for trailer lights doesn’t have to mean chasing wires or cutting into the factory harness. The Curt T-Connector uses a plug-in design that connects directly behind the tail lights. The connectors match up exactly with the factory plugs, so you get a clean install with no guesswork or splicing.
The built-in powered converter draws power directly from the vehicle’s battery instead of the tail light circuits. That keeps your vehicle’s wiring protected from overloads while powering your trailer lights reliably. It’s the right way to handle the extra load from trailer bulbs or LED lighting.
Once installed, the harness gives you a standard 4-flat trailer connector for running lights, turn signals, and brake lights. It’s the same connector used on most small and mid-size trailers, so you can hook up and go without any adapters or extra wiring.
Some users route the converter box and 4-flat plug into interior spaces like a spare tire well to protect them from rain and road salt. With its compact, hidden design and solid seals at connection points, it’s easy to keep everything tucked away and ready when you need it.
If you decide to add electric brakes or 12V trailer charging later, this harness is the first step. You can pair it with a universal 7-way installation kit to add those functions without starting over. It’s a simple way to grow your setup as your towing needs change.
Customer Satisfaction Score:
87% were satisfied with this product
13% of customers were not satisfied
Ratings & Reviews
When ordering the wiring harness I asked about installation. They told me it is a custom harness that just plugs in line with the vehicle brake lights. I received the harness and this is not the case. The rep that initially spoke to me about the harness clearly did not know what they were talking about. Still not that complicated but significantly more complicated than getting an OEM 4 pin connector kit.
Wires are too short and it really makes installation a pain. Both "legs" of the wires that lead to the rear light assemblies of the car are not long enough, especially the single green wire going to the passenger side. But the driver's side is also about 6"short, or at least another 6" would make it easier to install.
Running the power wire to the battery was easier than I anticipated. The toughest part was getting it up from the ground into the engine compartment.
Finally, if you're going to have to splice wires that are exposed, provide heat shrink butt splices so you have a chance of eliminating water and corrosion.
Solid wiring kit. Worked well and was relatively easy to install.
Installed on 2009 Honda Accord with V6. Piece of cake to install. I just use it for a bike rack that I already had. But note that I had an identical car with the 4 cylinder and I purchased the corresponding wiring harness and installed at the same time as a hitch on that vehicle as well, and I pulled a small trailer with a dirt bike for a couple of years. It worked out just fine. Never had any issues. High quality hitch and components. etrailer has always been really good to me.
this item would of worked but ended up sending back for the Factory lighting hook up because the factory one was plug n play much and easier for me to hook up. The factory one was more than triple the price but cleaner/professional install.
Great customer support!
Worked great and the install was easy e nough.
Installed on a 2024 Kia Sportage Hybrid.
The wires to the passenger taillight are way too short to make it easy. You have to get very crafty and get your arm in the cavity between the chassis and exterior bumper to make it work. Took me about 2 hours but eventually got it.
The video they provide is comical. You buy a kit, and a kit is usually everything you could possibly need to do the install with ease. The guy in the video then cuts the wires and adds more, uses shrink tubing, etc to get the kit to work. So even when they made the video they knew it wouldn’t work.
Plug and play so that was nicel, but if you have no experience or intuition working with your hands or a car, good luck, because you’ll need to spend way more money to get it to work if you have zero experience.
Simple fix to eTrailer, if you don’t want negative feedback on this product, extended the wires to a realistic length, it isn’t that hard.
Hitch was easy to install. Wiring took some time but when done everything worked. Is
fast and easy, delivered ahead of time
The wire harness looks easy to install. It is not. I had to remove all the rear cargo area covers and the leftside rear light fixtures only to determine that the part does not match the light connectors on myy 2025 Kia Sorento HEV. I am sending it back.
Application said for 2024 kia sorento ex. But when I removed the tail lights connectors were not the same. I tested and spliced the wires to make it work. Works fine.
Works fine but needs longer wires to make installation easier. Just barely enough wire so you can’t really secure it well with the zip ties.
I had the harness installed by an installer in your installer list, West Tire and Auto Repair. They did a good install. In an install video on your website it was found that the green wire going to the passenger side tail light was too short. It was for my install my install also. Etrailer needs to look into this.
In addition to the trailer hitch not having the mounting hardware (that I had to get myself and pay overnight shipping because they didn't have in stock) they sent the wrong harness for my vehicle even though I confirmed my VIN for assurance that I was getting the correct parts. When all is said and done, the cost will now exceed the price the dealer quoted for OEM parts. Epic fail.
It was fairly easy to install, and it worked great.
This fit on my 2026 Kia Sportage.
The packaging was destroy when i received it and i cannot upload my picture too show you
Easy to install. Wasn't short on wire as other reviews have mentioned. Works great.
This project took me more time to install than I expected. I'm in my mid 70's and move a little slower nowadays. I followed the instructions and plugged in the trailer and everything works just fine. The only problem I did encounter was the green wire was to short and I had to add a little more wire.
The wiring harness is as advertised and a good quality. The real reason I give the purchase five stars is because of the company and the employees that worked with me, help me with my order and kept me informed every step of the way. It’s refreshing to actually good get good customer service.
Alan
10/17/2025
I ordered the wrong part and they fixed it for me. It was totally my mistake, and I contacted them, and explained my problem. I expected it to be a lot of problems to correct, but they simply sent the correct item and credited once I return the wrong one. I saw someone else say the same thing in these reviews that a wiring harness is pretty basic I would order from these people again because of the customer service
Haven't installed yet but looks pretty simple. Read the manual completely and watch a few of the Utube videos. This wiring harness is really well engineered so there shouldn't be any problem.
DIFFERENT WAY TO INSTALL CURT WIRING HARNESS on Kia Sportage
II just purchased a 2025 Kia Sportage Hybrid and ordered the Curt wiring harness for it. When it arrived I did not like what the instructions said, mounting the electric module outside under the car along with 4 pin plug for the trailer. I looked for ways to mount everything in the spare tire well and did it as follows.
First I added one foot of wire to the four wires that go to the drivers’ side light. (See Picture) In hind site you could do only three because the white ground wire been place in the spare tire well.
Second I removed the plastic piece where the rear hatch locks on to. The are two push pins to remove and just pull it up the black panel that runs across the bottom. I then removed the weather stripping from the light down to where the spare tire area is. I then cut a ½” slot in the piece of metal that the weather stripping slides onto near the light using a Dremel, I filed it smooth and wrapped electrical tap around the four wires where it went thru the slot to protect them. (See Picture) near the light. I then work the wire up from the spare tire compartment slipping the wire under the plastic to the slot and then behind the drivers side light. I then screwed in the ground wire. (See Picture) I plugged the two connectors in, and reinstalled the drivers side light See picture of driver side light reinstalled. Next I extended the green wire going to the passenger light by 1 foot. I ran the wire to the passenger side of the spare tire well. Next with my Dremel cut a small slot maybe 1/8” wide so the green wire would fit in it. Just like the drivers side I ran the wire up into the plastic which is covered by the weather stripping, thur the slot and then plugged the two connectors in and then reinstalled the light.
Last thing was to get the power wire installed to the electrical module in the spare tire well. I connected to the spot in the picture near where you jump the car.(hybrid does not have regular 12 battery) See Picture. I then ran wire along both of driver side of the car, zip tying it along the way. In the spare tire well there is a plug left of the spare tire I pulled out and used the end of my pointed testing light to poke and hole thru it. Look down where that plug was, you can see light, which is where there is a plug in the frame. I pulled that plug out, it already has a whole in it, ran wire thru it, and it was easy to get wire into hole in the spare tire compartment. I then push wire thru that plug and re-inserted plugs,both on the frame and in the tire well. Very good seal going thru the plug in tire well. (see pictures). I connected power well under the hood and then connected power wire to the black wire on the electric module.
I now test the output on the trailer plug and everything was good. I re-installed the plastic piece running across the back under where the hatch closes and I was done.
The electric module and the trailer plug are now inside the spare tire compartment, out of the weather, and all I have to do is lift the lid of the spare tire a little and let the plug hang down to the bumper and plug my trailer in.
In the etrailer installation video, the installer states that you will need to splice in a segment of wire for the passenger (green) side for this kit.
Not being a fan of splicing in additional potential failure points, I tried to install this by not placing the module before running the wire, along with installing it BEFORE installing the hitch.
Doing the wiring FIRST made install considerably easier.
And in doing my process, I was able to fish the green wire across the back but ABOVE the rear bumper mount brackets which you would have very limited access to if you install the hitch first.
Doing it in this manner, the wire BARELY fits without splicing, so it can be done but Curt most certainly needs to add about 3"-6" of wiring to the green side in order for better fitment.
And running that wire up to the front for battery access is not the easiest, especially for an OCD person like me who does not like exposed wiring so yes I do disassemble trim on the vehicle to run the wire.
Wiring harness and hitch were easy to install with the included instructions. Harness does require several extra feet of wire and extra butt connectors to reach the passenger side tail light. Otherwise, easy installation.
Easy to find part, fit correctly for my vehicle make and model. All of the tutorial videos for the Tow bar and T-connector here made assembly super easy. I had it all connected and ready to tow within an hour or so!
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Gwendolyn Y.
11/25/2024
Hey Thomas. That doesn't sound like a pleasant experience. I do see you spoke to William and he's going to make sure you get a full refund on your order.